Evaluation of meteorological drought of the Black Sea Region using different mapping techniques

Evaluating the spatial change as well as the temporal change of drought enables the identification of risky regions in terms of drought within the study region. In this thesis study, Inverse Distance Weighted Interpolation, Kriging and Radial Basis Function mapping techniques were used to map the Black Sea Region meteorological drought, and the drought modeling success of these techniques was determined with different statistical test criteria. In addition to comparing different mapping techniques for mapping meteorological drought, the changes of Standardized Precipitation Index (SPI), Reconnaissance Drought Index (RDI), Erinc, De Martonne and De Martonne-Gottman methods in drought temporal analysis in different data periods were examined. In the spatial distribution of drought between 1965-2020, the Inverse Distance Weighted Interpolation (IDW) technique in the De Martonne and De Martonne-Gottman and Erinç methods, the Kriging technique in the SPI method and Radial Base Function (RBF) technique in the RDI method were the best mapping methods. It has been determined that the use of different input parameters in calculating drought index values affects the success of the mapping technique. From the spatial evaluation of drought, it was determined that drought occurrence was greater in the central part of the region within the borders of Yeşilırmak basin by De Martonne, De Martonne-Gottman and Erinç methods, and in the western part of the region by SPI and RDI methods. Drought and the formation of different drought classes had different rates in the first (1965-1992), second (1993-2020) and all (1965-2020) periods. It has been determined that the eastern part of the study region is the region with the lowest drought risk for all drought analysis methods and periods, and the climate class with the most severe index value of the rainy class occurs in this region. It has been evaluated that the flood risk, not the drought risk, is high in this region.